From 4c3698e5a76314911beaa8cfd45e1e14b34d95ee Mon Sep 17 00:00:00 2001
From: lpy <pylaurent1314@gmail.com>
Date: Wed, 12 Feb 2014 23:39:21 +0800
Subject: [PATCH] return value/use extra::test::black_box in benchmarks

---
 src/libcollections/bitv.rs   |  8 ++++++++
 src/libcollections/deque.rs  |  3 ++-
 src/libstd/io/buffered.rs    |  4 ++--
 src/libstd/mem.rs            | 12 ++++++------
 src/libstd/rt/global_heap.rs |  4 ++--
 src/libstd/str.rs            |  6 +++---
 src/libstd/vec.rs            | 19 +++++++++++--------
 7 files changed, 34 insertions(+), 22 deletions(-)

diff --git a/src/libcollections/bitv.rs b/src/libcollections/bitv.rs
index 7211907f48321..ceedb5d143ac0 100644
--- a/src/libcollections/bitv.rs
+++ b/src/libcollections/bitv.rs
@@ -1562,6 +1562,7 @@ mod tests {
         let mut bitv = 0 as uint;
         b.iter(|| {
             bitv |= (1 << ((r.next_u32() as uint) % uint::BITS));
+            &bitv
         })
     }
 
@@ -1571,6 +1572,7 @@ mod tests {
         let mut bitv = SmallBitv::new(uint::BITS);
         b.iter(|| {
             bitv.set((r.next_u32() as uint) % uint::BITS, true);
+            &bitv
         })
     }
 
@@ -1580,6 +1582,7 @@ mod tests {
         let mut bitv = BigBitv::new(~[0]);
         b.iter(|| {
             bitv.set((r.next_u32() as uint) % uint::BITS, true);
+            &bitv
         })
     }
 
@@ -1591,6 +1594,7 @@ mod tests {
         let mut bitv = BigBitv::new(storage);
         b.iter(|| {
             bitv.set((r.next_u32() as uint) % BENCH_BITS, true);
+            &bitv
         })
     }
 
@@ -1600,6 +1604,7 @@ mod tests {
         let mut bitv = Bitv::new(BENCH_BITS, false);
         b.iter(|| {
             bitv.set((r.next_u32() as uint) % BENCH_BITS, true);
+            &bitv
         })
     }
 
@@ -1609,6 +1614,7 @@ mod tests {
         let mut bitv = Bitv::new(uint::BITS, false);
         b.iter(|| {
             bitv.set((r.next_u32() as uint) % uint::BITS, true);
+            &bitv
         })
     }
 
@@ -1618,6 +1624,7 @@ mod tests {
         let mut bitv = BitvSet::new();
         b.iter(|| {
             bitv.insert((r.next_u32() as uint) % uint::BITS);
+            &bitv
         })
     }
 
@@ -1627,6 +1634,7 @@ mod tests {
         let mut bitv = BitvSet::new();
         b.iter(|| {
             bitv.insert((r.next_u32() as uint) % BENCH_BITS);
+            &bitv
         })
     }
 
diff --git a/src/libcollections/deque.rs b/src/libcollections/deque.rs
index 325f0ee4edb63..14c6bc5ce281a 100644
--- a/src/libcollections/deque.rs
+++ b/src/libcollections/deque.rs
@@ -115,8 +115,9 @@ pub mod bench {
         // measure
         let mut i = 0;
         bh.iter(|| {
-            map.find(&i);
+            let x = map.find(&i);
             i = (i + 1) % n;
+            x
         })
      }
 }
diff --git a/src/libstd/io/buffered.rs b/src/libstd/io/buffered.rs
index a48403f19a480..346a962af19bc 100644
--- a/src/libstd/io/buffered.rs
+++ b/src/libstd/io/buffered.rs
@@ -565,14 +565,14 @@ mod test {
     #[bench]
     fn bench_buffered_reader(bh: &mut Harness) {
         bh.iter(|| {
-            BufferedReader::new(NullStream);
+            BufferedReader::new(NullStream)
         });
     }
 
     #[bench]
     fn bench_buffered_writer(bh: &mut Harness) {
         bh.iter(|| {
-            BufferedWriter::new(NullStream);
+            BufferedWriter::new(NullStream)
         });
     }
 
diff --git a/src/libstd/mem.rs b/src/libstd/mem.rs
index 09d2db329ca03..ee05d6a704bed 100644
--- a/src/libstd/mem.rs
+++ b/src/libstd/mem.rs
@@ -292,7 +292,7 @@ mod bench {
         let s = Struct { field: 10 };
         let t = &s as &Trait;
         bh.iter(|| {
-            t.method();
+            t.method()
         });
     }
 
@@ -300,7 +300,7 @@ mod bench {
     fn trait_static_method_call(bh: &mut BenchHarness) {
         let s = Struct { field: 10 };
         bh.iter(|| {
-            s.method();
+            s.method()
         });
     }
 
@@ -310,10 +310,10 @@ mod bench {
     fn match_option_some(bh: &mut BenchHarness) {
         let x = Some(10);
         bh.iter(|| {
-            let _q = match x {
+            match x {
                 Some(y) => y,
                 None => 11
-            };
+            }
         });
     }
 
@@ -321,10 +321,10 @@ mod bench {
     fn match_vec_pattern(bh: &mut BenchHarness) {
         let x = [1,2,3,4,5,6];
         bh.iter(|| {
-            let _q = match x {
+            match x {
                 [1,2,3,..] => 10,
                 _ => 11
-            };
+            }
         });
     }
 }
diff --git a/src/libstd/rt/global_heap.rs b/src/libstd/rt/global_heap.rs
index 2f553585f38ce..7ecfb3ff7ba5c 100644
--- a/src/libstd/rt/global_heap.rs
+++ b/src/libstd/rt/global_heap.rs
@@ -140,14 +140,14 @@ mod bench {
     #[bench]
     fn alloc_owned_small(bh: &mut BenchHarness) {
         bh.iter(|| {
-            ~10;
+            ~10
         })
     }
 
     #[bench]
     fn alloc_owned_big(bh: &mut BenchHarness) {
         bh.iter(|| {
-            ~[10, ..1000];
+            ~[10, ..1000]
         })
     }
 }
diff --git a/src/libstd/str.rs b/src/libstd/str.rs
index bc5991c6eebd0..e1a9b512eecc3 100644
--- a/src/libstd/str.rs
+++ b/src/libstd/str.rs
@@ -4356,7 +4356,7 @@ mod bench {
 
         assert_eq!(100, s.len());
         bh.iter(|| {
-            let _ = is_utf8(s);
+            is_utf8(s)
         });
     }
 
@@ -4365,7 +4365,7 @@ mod bench {
         let s = bytes!("𐌀𐌖𐌋𐌄𐌑𐌉ปรدولة الكويتทศไทย中华𐍅𐌿𐌻𐍆𐌹𐌻𐌰");
         assert_eq!(100, s.len());
         bh.iter(|| {
-            let _ = is_utf8(s);
+            is_utf8(s)
         });
     }
 
@@ -4408,7 +4408,7 @@ mod bench {
     #[bench]
     fn bench_with_capacity(bh: &mut BenchHarness) {
         bh.iter(|| {
-            let _ = with_capacity(100);
+            with_capacity(100)
         });
     }
 
diff --git a/src/libstd/vec.rs b/src/libstd/vec.rs
index 2acafecf95720..493d57fa9cfc7 100644
--- a/src/libstd/vec.rs
+++ b/src/libstd/vec.rs
@@ -4385,6 +4385,7 @@ mod bench {
         let mut vec: ~[uint] = ~[0u];
         bh.iter(|| {
             vec.push(0);
+            &vec
         })
     }
 
@@ -4392,7 +4393,7 @@ mod bench {
     fn starts_with_same_vector(bh: &mut BenchHarness) {
         let vec: ~[uint] = vec::from_fn(100, |i| i);
         bh.iter(|| {
-            vec.starts_with(vec);
+            vec.starts_with(vec)
         })
     }
 
@@ -4400,7 +4401,7 @@ mod bench {
     fn starts_with_single_element(bh: &mut BenchHarness) {
         let vec: ~[uint] = ~[0u];
         bh.iter(|| {
-            vec.starts_with(vec);
+            vec.starts_with(vec)
         })
     }
 
@@ -4410,7 +4411,7 @@ mod bench {
         let mut match_vec: ~[uint] = vec::from_fn(99, |i| i);
         match_vec.push(0);
         bh.iter(|| {
-            vec.starts_with(match_vec);
+            vec.starts_with(match_vec)
         })
     }
 
@@ -4418,7 +4419,7 @@ mod bench {
     fn ends_with_same_vector(bh: &mut BenchHarness) {
         let vec: ~[uint] = vec::from_fn(100, |i| i);
         bh.iter(|| {
-            vec.ends_with(vec);
+            vec.ends_with(vec)
         })
     }
 
@@ -4426,7 +4427,7 @@ mod bench {
     fn ends_with_single_element(bh: &mut BenchHarness) {
         let vec: ~[uint] = ~[0u];
         bh.iter(|| {
-            vec.ends_with(vec);
+            vec.ends_with(vec)
         })
     }
 
@@ -4436,7 +4437,7 @@ mod bench {
         let mut match_vec: ~[uint] = vec::from_fn(100, |i| i);
         match_vec[0] = 200;
         bh.iter(|| {
-            vec.starts_with(match_vec);
+            vec.starts_with(match_vec)
         })
     }
 
@@ -4444,7 +4445,7 @@ mod bench {
     fn contains_last_element(bh: &mut BenchHarness) {
         let vec: ~[uint] = vec::from_fn(100, |i| i);
         bh.iter(|| {
-                vec.contains(&99u);
+            vec.contains(&99u)
         })
     }
 
@@ -4464,13 +4465,14 @@ mod bench {
                 ptr::set_memory(vp, 0, 1024);
                 v.set_len(1024);
             }
+            v
         });
     }
 
     #[bench]
     fn zero_1kb_fixed_repeat(bh: &mut BenchHarness) {
         bh.iter(|| {
-            let _v: ~[u8] = ~[0u8, ..1024];
+            ~[0u8, ..1024]
         });
     }
 
@@ -4499,6 +4501,7 @@ mod bench {
             for x in v.mut_iter() {
                 *x = 0;
             }
+            v
         });
     }